An issue was discovered in Django 2.0 before 2.0.3, 1.11 before 1.11.11, and 1.8 before 1.8.19. The django.utils.html.urlize() function was extremely slow to evaluate certain inputs due to catastrophic backtracking vulnerabilities in two regular expressions (only one regular expression for Django 1.8.x). The urlize() function is used to implement the urlize and urlizetrunc template filters, which were thus vulnerable.
https://www.djangoproject.com/weblog/2018/mar/06/security-releases/
https://lists.debian.org/debian-lts-announce/2018/03/msg00006.html
http://www.securityfocus.com/bid/103361
https://usn.ubuntu.com/3591-1/
https://www.debian.org/security/2018/dsa-4161
https://access.redhat.com/errata/RHSA-2018:2927
https://access.redhat.com/errata/RHSA-2019:0082
Source: MITRE
Published: 2018-03-09
Updated: 2021-08-04
Type: CWE-185
Base Score: 5
Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P
Impact Score: 2.9
Exploitability Score: 10
Severity: MEDIUM
Base Score: 5.3
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Impact Score: 1.4
Exploitability Score: 3.9
Severity: MEDIUM